import { describe, expect, it } from "vitest";

import {
  catalogKeys,
  FORMAT_FALLBACK,
  formatDate,
  formatList,
  formatMessage,
  formatNumber,
  formatRelativeTime,
  localeDirection,
  messagePlaceholders,
  normalizeLocale,
  resolveMessage,
  selectMessage,
  selectPlural,
} from "../../src/presentation/i18n/index.js";
import {
  EN_MESSAGES,
  KO_MESSAGES,
  MESSAGE_CATALOGS,
} from "../../src/presentation/i18n/catalog.js";

describe("internationalization message contract", () => {
  it("keeps every registered catalog and interpolation contract in parity", () => {
    expect(catalogKeys("en-US")).toEqual(catalogKeys("ko-KR"));
    expect(catalogKeys("ar-EG")).toEqual(catalogKeys("ko-KR"));

    for (const key of catalogKeys("ko-KR")) {
      expect(messagePlaceholders(EN_MESSAGES[key])).toEqual(
        messagePlaceholders(KO_MESSAGES[key]),
      );
    }
    expect(MESSAGE_CATALOGS["ar-EG"]).toBe(EN_MESSAGES);
  });

  it("formats typed parameters and expands the pseudo locale", () => {
    expect(
      formatMessage("en-US", "route.documentTitle", {
        title: "Settings",
        appName: "Skeleton",
      }),
    ).toBe("Settings · Skeleton");
    const pseudo = formatMessage("en-XA", "action.closeNamed", {
      title: "Account",
    });
    expect(pseudo).toMatch(/^［.+ ···］$/);
    expect(pseudo.length).toBeGreaterThan("Close Account".length);
  });

  it("falls back safely for unknown locale, key and missing interpolation", () => {
    expect(normalizeLocale("fr-FR")).toBe("ko-KR");
    expect(resolveMessage("fr-FR", "action.retry")).toBe("다시 시도");
    expect(resolveMessage("en-US", "action.login")).toBe("Sign in");
    expect(resolveMessage("en-US", "backend.stack.trace")).toBe(
      "요청한 문구를 표시할 수 없습니다.",
    );
    expect(resolveMessage("en-US", "action.closeNamed")).toBe(
      "요청한 문구를 표시할 수 없습니다.",
    );
    expect(resolveMessage("en-US", "backend.stack.trace")).not.toContain(
      "backend.stack.trace",
    );
  });

  it("defines direction without inferring it in components", () => {
    expect(localeDirection("ko-KR")).toBe("ltr");
    expect(localeDirection("en-XA")).toBe("ltr");
    expect(localeDirection("ar-EG")).toBe("rtl");
  });
});

describe("internationalization formatter contract", () => {
  const instant = new Date("2026-07-26T23:30:00.000Z");

  it("uses an explicit UTC default and deterministic locale formatting", () => {
    expect(formatDate("en-US", instant, { dateStyle: "short" })).toBe(
      "7/26/26",
    );
    expect(
      formatDate("en-US", instant, {
        dateStyle: "short",
        timeZone: "Asia/Seoul",
      }),
    ).toBe("7/27/26");
    expect(formatNumber("en-US", 1234.5)).toBe("1,234.5");
    expect(formatRelativeTime("en-US", -1, "day")).toBe("yesterday");
    expect(formatList("en-US", ["one", "two", "three"])).toBe(
      "one, two, and three",
    );
    expect(selectPlural("en-US", 1, { one: "item", other: "items" })).toBe(
      "item",
    );
    expect(
      selectPlural("en-US", 3, { one: "item", other: "items" }),
    ).toBe("items");
    expect(
      selectMessage("pending", {
        ready: "Ready",
        pending: "Pending",
        other: "Unknown",
      }),
    ).toBe("Pending");
  });

  it("does not throw or expose invalid formatter input", () => {
    expect(formatDate("en-US", Number.NaN)).toBe(FORMAT_FALLBACK);
    expect(formatNumber("en-US", Number.POSITIVE_INFINITY)).toBe(
      FORMAT_FALLBACK,
    );
    expect(
      formatDate("en-US", instant, { timeZone: "not/a-time-zone" }),
    ).toBe(FORMAT_FALLBACK);
  });
});